Who said June was the slow time of year for college football?

To the surprise of many, the nation’s longest-tenured FBS coach at his current school is reportedly stepping down.

According to a report from the Oklahoman’s Berry Tramel, Oklahoma coach Bob Stoops will announce his retirement, effective immediately.

Tramel reported that 33-year-old offensive coordinator Lincoln Riley will take over as the program’s new head coach.

Stoops, a former Iowa defensive back, has been with the Sooners since 1999. He won the 2000 National Championship and earned 10 Big 12 titles during his 18 seasons at Oklahoma.

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Long before Stoops became one of college football’s top coaches, he was an assistant on Hayden Fry’s staff at Iowa from 1983-87.

He previously held the title of the nation’s longest-tenured coach at his current school. But with his retirement, that title will now belong to Kirk Ferentz, who arrived in Iowa City a week after Stoops took over in Norman.

Oklahoma is set to take on Ohio State in Week 2 of the 2017 season. With Stoops on the sidelines last year, the Buckeyes cruised to a 45-24 victory in Norman.